SDR ASAA2020092033203

Service difficulty report · Autopilot Sys · Boeing 737890

Difficulty date: September 20, 2020
Submitted: September 22, 2020
Operation: Air carrier
Aircraft: N593AS
Make and model: Boeing 737890
Aircraft serial: 35107
Aircraft time: 46,436 hours, 13,988 cycles
System (JASC): 2210 · Autopilot System
Part: Autopilot Sys
Condition: Disconnected
Location: A System
Stage of operation: CR
How discovered: O
Nature of condition: J
Precautionary procedure: O

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

AT CRZ FL380, SMOOTH AIR, AUTOPILOT "A" DISENGAGED FOR NO APPARENT REASON. ALL SYSTEM & ENGINE INDICATIONS WERE NORMAL AT THE TIME. AUTO PILOT "A" WAS REENGAGED WITH NO FURTHER ISSUES. GROUNDED-YES. PERFORMED DFCS OPS TEST/AUTOTEST, IAW B737-800 AMM 22-11-00-740-801, NO FAULTS CURRENT. RAN ADDITIONAL TEST FOR AUTOPILOT A+B, DUAL CHANNEL, ALL TEST PASS. AUTOPILOT "A" DISCONNECT WAS PRESENT IN FAULT HISTORY, REF B737-800 AMM 22-10-00-740-806.